1. Field of the Invention
This invention relates to organotin compounds containing fluorine which are useful in forming fluorine-doped tin oxide coatings.
2. Description of the Prior Art
The following are prior art references which describe compounds related to those of the present invention, which, however, do not have the attributes required to form liquid coating compositions for chemical vapor deposition.
Menke, in U.S. Pat. No. 3,759,743, described the preparation of non-halogenated organotin trifluoroacetates, and compositions thereof in organic solvents, such as methyl ethyl ketone, for making fluorine-doped tin-oxide coatings by the spray solution method. These precursors, however, have a low volatility and are unsuitable for the more advantageous chemical vapor deposition process where no solvent is added.
Wang and Shreeve, in Chemical Communications (1970) page 151, and J. Organomet. Chem. 38 (1972) page 287, describe the preparation of dialkylchlorotin trifluoroacetates. Such compounds, unfortunately, are solids which cannot be used in chemical vapor deposition process.
Bost, et al., in U.S. Pat. No. 4,093,636, describes related non-fluorinated organotin compounds, which cannot be used to provide fluorine-doped tin oxide coatings.
Plum, et al., in U.S. Pat. No. 4,374,778, discloses fluoroorganotin compounds in which the fluorine atom is bonded directly to the tin atom.
Franz, et al., in U.S. Pat. No. 4,254,046, disclose dialkyltin difluorides for powder deposition of fluorine-doped tin oxide coatings.
Thompson in French Pat. No. 1,400,314 describes mono, di- and trialkyltin trifluoroacetates and their preparation.
Liberte, Reiff and Davidsohn, in Organic Preparation and Procedures 1 (3) 173-176 (1969), describe the preparation of dialkyltin polyfluoro carboxylates.
An article in J. Organomet. Chem., (3) 151 (1970), describes a dialkylchlorotin trifluoromethyl acetate.
J. Organomet. Chem. 3972 (1971) describes trialkyltin perfluoroalkyl oxides.
These references do not disclose an organotin precursor useful for chemical vapor deposition particularly from a liquid coating composition. Moreover, the references do not disclose an organotin compound which has a monoalkyl or related substituent and at least one chlorine atom attached directly to the tin atom, and at least one trifluoromethyl-containing constituent.
Accordingly, an object of this invention is to provide new and improved organotin compounds which may be used directly to form fluorine doped tin oxide coatings having a low sheet resistance.
Another object herein is to provide such compounds which may be used to prepare fluorine-doped tin oxide coatings such as by the chemical vapor deposition method.
Still another object herein is to prepare monoalkylchlorotin trifluoracetates and related compounds which can be used advantageously in liquid coating compositions for chemical vapor deposition of fluorine-doped tin oxide coatings.